20104439977 has 2 divisors, whose sum is σ = 20104439978. Its totient is φ = 20104439976.

The previous prime is 20104439959. The next prime is 20104439987. The reversal of 20104439977 is 77993440102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13120327936 + 6984112041 = 114544^2 + 83571^2 .

It is a cyclic number.

It is not a de Polignac number, because 20104439977 - 2²⁷ = 19970222249 is a prime.

It is not a weakly prime, because it can be changed into another prime (20104439947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10052219988 + 10052219989.

It is an arithmetic number, because the mean of its divisors is an integer number (10052219989).

Almost surely, 2^20104439977 is an apocalyptic number.

It is an amenable number.

20104439977 is a deficient number, since it is larger than the sum of its proper divisors (1).

20104439977 is an equidigital number, since it uses as much as digits as its factorization.

20104439977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 381024, while the sum is 46.

The spelling of 20104439977 in words is "twenty billion, one hundred four million, four hundred thirty-nine thousand, nine hundred seventy-seven".